Insulator supporting rack



M y 1955 F. c. VOSE ETAL INSULATOR SUPPORTING RACK Filed 17, 1950 5 6 ZM w 4 8 8 8 W 8 H w \I1II1iI1 0.x h 0. 7 4-. m m a 4 w 9 0. 4 i a H w wL 0 w J 6 ATTORNEY United States Patent IN SULATOR SUPPORTING RACK FredC. Vose, Glen Burnie, and Bernard W. Ruth, Baltimore, Md., assignors toGeneral Electric Company, a corporation of New York Application August17, 1950, Serial No. 179,972

1 Claim. (Cl. 248-67.7)

This invention relates to an insulator supporting rack and, moreparticularly, to an insulator supporting rack of the type known as asecondary rack, or service rack and to a method of making the same.

The term secondary rack is generally used to describe an insulatorsupport by which a plurality of insulators are supported in alignmentand these insulators, in turn, support low voltage electric linesconnected to the secondary system of a transformer. For the usual threewire low voltage distribution system, three spool type insulators areused and these insulators are supported in vertical alignment by meansof a secondary rack which is mounted in upright position on a supportpole, building, etc. These racks, when mounted on buildings to supportwires serving the buildings, are also known as service racks.

Since secondary racks are used in large numbers, particularly in ruraland suburban areas, cost is an important factor in their design. Factorssuch as simplicity of manufacture, the material needed for fabrication,etc. of course affect cost.

It is therefore an object of our invention to provide a new and improvedlight weight and inexpensive secondary rack particularly adapted for usein connection with rural electric power distribution systems; and it isa further object of our invention to provide a new and improved methodfor making such a secondary rack.

Briefly stated, a secondary rack constructed in accordance with theteaching of our invention comprises an elongated channel shaped memberhaving laterally extending pairs of mounting pads spaced for mountingthe secondary rack in upright position against a support pole or thelike and correspondingly spaced pairs of arms extending perpendicularlyfrom the web of the channel shaped member adjacent the mounting pads forsupporting the insulators in properly spaced relation to each other andto the mounting pads. The channel member, mounting pads and insulatorsupporting arms are formed from a single piece of thin gauge sheetmetal, the insulator supporting arms being formed adjacent the mountingpads by partially severing opposite portions of the channel web andbending these partially severed portions towards each other into properposition with respect to the web and to the mounting pads. By virtue ofthe unitary construction of the rack and the simplicity of manufacture,the cost is favorable as compared to racks wherein different parts haveto be fitted together and yet, by suitable choice of materials, our rackwill due to the integral coordination of the insulator supporting armsand the mounting pads have enough strength for normal applicationsdespite its light weight and inexpensiveness.

These and other objects of our invention will become more apparent fromthe following detailed description taken in conjunction with theattached drawing in which Fig. 1 is a front elevation view of asecondary rack constructed in accordance with the teaching of ourinvention; Fig. 2 is a side elevation view of the secondary rack shownin Fig. 1; Fig. 3 is an end view of the secondary rack shown in Fig. 1;Fig. 4 is a view corresponding to that of Fig. 1 showing a blank formedduring the process of our invention; and Fig. 5 is an end view of theblank shown in Fig. 4.

As shown in Figs. 1-3, a preferred embodiment of our secondary rackincludes an elongated channel shaped member 1 having a web 2 andoppositely disposed sides 3. Each channel side 3 has a lateral flange 4extending therefrom throughout its length, these flanges being ofcorresponding size and shape and being symmetrically disposed withrespect to the channel web 2. The flanges 4 have further lateralextensions or spaced pairs of mounting pads 5 extending therefrom, thesepairs of mounting pads 5 being positioned adjacent each end of channelmember 1 and midway the length thereof as shown in Fig. 1. As will benoted from Fig. 1, corresponding extensions 5 forming each pair ofmounting pads project in opposite directions and the pairs of mountingpads 5 are symmetrically disposed with respect to channel memher 1, thusgiving the general appearance of pairs of sup porting ears. Eachmounting pad extension 5 contains an aperture 6 which is adapted toreceive a connecting member such as a bolt, screw or the like forattaching the secondary rack in upright position to a support ingstructure such as a support pole.

At each end of channel member 1, an insulator supporting arm 7 extendsat right angles with respect to the channel web 2 as shown in Figs. 2and 3. Each insulator supporting arm is integral with channel web 2 and,in effect, is an end right angle confirmation of the web. The otherinsulator supporting arms 8 are of a size and shape corresponding toarms '7, are located at intervals along the length or" channel member 1and between the ends thereof, and extend substantially at right anglesfrom channel web 2 in the same direction as do arms 7. As explained morefully hereinafter the intermediate insulator supporting arms 8 are bentup portions of the channel web 2 integral with the portion of thechannel web extending between the coordinate mounting pads 5 wherebysaid channel web contains gaps 9 corresponding in size and shape to thearms 8. Each of the arms 7 and 8 has an opening 10 adjacent its end andthese openings are aligned to receive a supporting rod 11 which extendsaxially through spool type insulators 12 as shown in Fig. 2.

As will be seen from an inspection of Fig. 2, each end insulatorsupporting arm 7 and the supporting arm 8 associated therewith, and thetwo middle supporting arms 8, provide brackets consisting of pairs ofcomplementary supporting arms and mounting pads. For each such bracket,the individual arms face toward each other and are spaced apartsubstantially the height of the insulator associated therewith so as toprevent this insulator from sliding along the supporting rod 11. Also,the respective pairs of insulator supporting arms and mounting padscomprising each bracket are spaced apart a predetermined distance fromeach other to provide proper spacing between individual insulators 12,and the rms are of suificient length to maintain these insulators at theproper distance from the channel member 1.

For example, in one size of a secondary rack made according to thepresent invention, the channel member 1 is 18%, inches long and thelength of each supporting arm 7 and 8 is 2 inches. For each end pair ofsupporting arms 7 and 8 and the middle pair of supporting arms 8, thetwo arms making up the pair are spaced 2% inches apart.

In making the secondary rack described above, a piece of thin gaugesheet metal (for example No. 14 gauge sheet steel) is formed into anelongated blank having a channel shaped cross section and laterallyextending flanges as shown in Figs. 4 and 5. This forming of the blankmay be accomplished by die forming the metal into the shape described.Either before or after the aforementioned forming operation, the earlikespaced apart pairs of mounting pad extensions 5 and tongues in may bestamped or otherwise cut out to provide the configuration shown in Figs.4 and 5.

The channel web 2 is then out along dotted lines 13 to form portions 8awhich are of size and shape corresponding to tongues 7a. Being thusfreed, portions 8a may then be bent up at right angles to the channelweb 2 to provide the insulator supporting arms 8 previousiy described.Since these portions 8a are bent up it is obvious that the gaps 9 willbe left in the channel web 2. The extending tongue portions 7a are alsobent up at right angles to the channel web 2 to form insulatorsupporting arms 7. As previously mentioned, and as can be readilyobserved from an inspection of Pig. 3, the indivdual supporting arms ineach pair of supporting arms are bent up to face each other. Thus, theend portions 7a are bent up toward each other, the web portions 3aadjacent the ends of channel member 1 are bent up away from each other,and the two middle web portions 8a are bent up toward each other. Afterbeing formed as thus described the secondary rack is preferablygalvanized.

From the foregoing description it is seen that we provide a secondaryrack in which the rack structure per se is formed entirely from a singlesheet of metal. This is found to contribute to simplicity of manufactureand reduction in cost. Using No. 14 gauge sheet steel, as an example, itis found that the rack is relatively light weight as compared tocomparable racks on the market and yet has sufficient strength fornormal applications. It is particularly adapted for use to support lowvoltage electric distribution lines in rural regions.

Although, in the preceding description and attached drawing, we makereference to three pairs of insulator supporting arms, it is obviousthat more or less than three pairs may be provided in a structure madeaccording to the teaching of our invention. Also, these insulatorsupporting arms may be used to support other types of ina sulators thanspool type insulators, for example, wire holder type insulators. Whilewe have indicated thin gauge sheet steel as being a preferable materialfrom which to form our secondary rack, it is obvious that othermaterials could be employed provided they have the requisite strengthand workability.

Therefore, while we have described and illustrated a particularembodiment of our invention we wish it to be understood that we do notintend to be restricted solely thereto but that we do intend to coverall modifications thereof which would occur to one skilled in the artand which come within the spirit and scope of our invention.

Having thus described our invention, what is claimed as new and desiredto be secured by Letters Patent is:

A supporting rack comprising an elongated channel shaped member havingtwo lengthwise extending sides connected by a lengthwise extendingintegral web, each of said sides having a lengthwise extending integralflange thereon extending generally perpendicular therefrom, an endmostsupporting arm disposed at each end of said elongated member, said twoendmost arms comprising integral continuations of said web extendinglengthwise beyond opposite ends of said elongated member and then benttowards each other, two other supporting arms, said other arms disposedinwardly of said opposite ends and spaced from and connected to said twoendmost arms by a portion of said web, said two other arms comprisingintegral continuations of said web extending towards each other and thenbent away from each other, and another two supporting arms disposedopposite to each other adjacent a central portion of said elongatedmember, said another two arms comprising integral continuations of saidweb extending away from each other and then bent towards each other,said another two arms spaced from each other and interconnected by aportion of said web, openings in said web formerly occupied by said twoother and said another two supporting arms spaced from each other bycontinuations of said web, a pair of integral mounting pads extendingfrom said flanges disposed adjacent each of said web portions, all ofsaid bent continuations protruding from an identical surface of sai web.

References tilted in the file of this patent UNlTED STATES PATENTS1,123,107 Darr Dec. 29, 1914 1,685,684 Smalley Sept. 25, 1928 1,779,489Peirce Oct. 28, 1930 1,811,211 Peirce June 23, 1931 1,853,218 MillerApr. 12, 1932 1,990,667 Peirce Feb. 13, 1935 2,103,415 Greenwood Dec.28, 1937 2,300,673 Johns Nov. 3, 1942 2,300,674 Johns Nov. 3, 1942

